Ethanol-물 혼합용매 중에서 Tetraalkylammonium Halides, Me₄NI, Et₄NI, Pr₄NI, Bu₄NI, Me₄NBr, Pr₄NBr, Me₄NCl, 및 Pr₄NCl의 분몰랄 부피를 30 ℃에서 측정한 결과 Halides 이온은 모든 용매 조성에 있어서 그 크기가 커짐에 따라 V⁰x가 증가하고, 0.3 몰 분율에서 최소치를 갖는다. 이것은 이 조성에서 electrostrictive effect가 최대임을 나타내며, 또 V⁰x_R4N⁺이 0.1 몰 분율에서 공통적으로 최소치를 나타냄은 물은 이 조성에서 가장 강화되었음을 보여준다.

The partial molal volumes of a series of homologous tetraalkylammonium iodides, bromides and chlorides in a series of ethanol-water mixtures have been determined at 30 ℃. It was found that general trend in variation of anionic partial volumes V^o_x- with the solvent composition is the same for all the anions studied, i.e., Cl^-, Br^- and I^-, and that absolute values V^o_x-increase with the size of anions in all solvent compositions.
The results also indicate that at 0.1 mole fraction ethanol the maximum stucturedness of water causes a minimum in the tetraalkylammonium cation partial molal volumes, while at 0.2-0.3 mole fraction the solvent structure is such that the free volume is a minimum and the electrostrictive effect of halides ion is a maximum.